How to use head command to view first few lines of a file?

Using the head Command to View the First Few Lines of a File

The head command in Linux is a powerful tool that allows you to view the first few lines of a file. This can be particularly useful when you need to quickly inspect the contents of a file, especially when dealing with large files or files with an unknown structure.

Syntax and Options

The basic syntax for using the head command is as follows:

head [options] [file(s)]

Here are some common options you can use with the head command:

• -n <number>: Specifies the number of lines to display. For example, head -n 5 file.txt will display the first 5 lines of the file.
• -c <number>: Specifies the number of bytes to display. For example, head -c 20 file.txt will display the first 20 bytes of the file.
• -q: Suppresses the header that displays the filename when multiple files are specified.
• -v: Displays the filename when multiple files are specified.

Examples

Let's go through some examples to demonstrate how to use the head command:

1. Viewing the first 5 lines of a file:

$ head -n 5 file.txt

This will display the first 5 lines of the file file.txt.

2. Viewing the first 10 bytes of a file:

$ head -c 10 file.txt

This will display the first 10 bytes of the file file.txt.

3. Viewing the first few lines of multiple files:

$ head -n 3 file1.txt file2.txt file3.txt

This will display the first 3 lines of each file (file1.txt, file2.txt, and file3.txt).

4. Suppressing the filename header:

$ head -q -n 2 file1.txt file2.txt

This will display the first 2 lines of each file without the filename header.

Here's a Mermaid diagram that summarizes the key concepts of using the head command:

The head command is a simple yet powerful tool that can save you a lot of time when you need to quickly inspect the contents of a file. By understanding the various options and examples, you can effectively use the head command to streamline your workflow and better understand the data you're working with.